.\"	$OpenBSD: an.4,v 1.42 2015/02/28 05:47:36 mlarkin Exp $
.\"
.\" Copyright (c) 1997, 1998, 1999
.\"	Bill Paul <wpaul@ee.columbia.edu>. All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by Bill Paul.
.\" 4. Neither the name of the author nor the names of any co-contributors
.\"    may be used to endorse or promote products derived from this software
.\"   without specific prior written permission.
.\"
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
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.\" $FreeBSD: src/share/man/man4/an.4,v 1.5 2000/03/02 14:53:45 sheldonh Exp $
.\"
.Dd $Mdocdate: February 28 2015 $
.Dt AN 4
.Os
.Sh NAME
.Nm an
.Nd Aironet Communications 4500/4800 IEEE 802.11FH/b wireless network device
.Sh SYNOPSIS
.Cd "an* at pcmcia?"
.Cd "an* at pci?"
.Cd "an* at isapnp?"
.Sh DESCRIPTION
The
.Nm
driver provides support for the Aironet Communications 4500, 4800
(aka Cisco 340), and Cisco 350
IEEE 802.11 wireless network adapters.
This includes the ISA, PCI, and PCMCIA varieties.
The 4500 series adapters operate at 1 and 2Mbps (FH) while
the 4800 and 350 series can operate at 1, 2, 5.5, and 11Mbps (DS).
The ISA, PCI,
and PCMCIA devices are all based on the same core PCMCIA modules
and all have the same programming interface.
However, unlike the
Lucent WaveLAN/IEEE cards, the ISA and PCI cards appear to the
host as normal ISA and PCI devices and do not require any PCMCIA
support.
.Pp
ISA cards can either be configured to use ISA Plug and Play
or to use a particular I/O address and IRQ
by properly setting the DIP switches on the board.
(The default switch setting is for plug and play.)
The
.Nm
driver has Plug and Play support and will work in either configuration,
however when using a hard-wired I/O address and IRQ, the driver
configuration and the NIC's switch settings must agree.
PCI cards
require no switch settings of any kind and will be automatically
probed and attached.
.Pp
All host/device interaction with the Aironet cards is via programmed I/O.
The
.Nm
driver encapsulates all IP and ARP traffic as 802.11 frames, though
it can receive either 802.11 or 802.3 frames.
.Pp
These are the modes the
.Nm
driver can operate in:
.Bl -tag -width "IBSS-masterXX"
.It BSS mode
Also known as
.Em infrastructure
mode, this is used when associating with an access point, through
which all traffic passes.
This mode is the default.
.It IBSS mode
Also known as
.Em IEEE ad-hoc
mode or
.Em peer-to-peer
mode.
This is the standardized method of operating without an access point.
Stations associate with a service set.
However, actual connections between stations are peer-to-peer.
.It monitor mode
In this mode the driver is able to receive packets without
associating with an access point.
This disables the internal receive filter and enables the card to
capture packets from networks which it wouldn't normally have access to,
or to scan for access points.
.El
.Pp
The
.Nm
driver can be configured to use hardware
Wired Equivalent Privacy (WEP).
It is strongly recommended that WEP
not be used as the sole mechanism
to secure wireless communication,
due to serious weaknesses in it.
.Pp
The
.Nm
driver can be configured at runtime with
.Xr ifconfig 8
or on boot with
.Xr hostname.if 5 .
.Sh EXAMPLES
The following
.Xr hostname.if 5
example configures an0 to join network
.Dq mynwid ,
using WEP key
.Dq mywepkey ,
obtaining an IP address using DHCP:
.Bd -literal -offset indent
nwid mynwid
nwkey mywepkey
dhcp
.Ed
.Sh DIAGNOSTICS
.Bl -diag
.It "an0: failed to allocate N bytes on NIC"
The driver was unable to allocate memory for transmit frames in the
NIC's on-board RAM.
.It "an0: device timeout"
The Aironet card failed to generate an interrupt to acknowledge a transmit
command.
.El
.Sh SEE ALSO
.Xr arp 4 ,
.Xr ifmedia 4 ,
.Xr intro 4 ,
.Xr isapnp 4 ,
.Xr netintro 4 ,
.Xr pci 4 ,
.Xr pcmcia 4 ,
.Xr hostname.if 5 ,
.Xr ifconfig 8
.Sh HISTORY
The
.Nm
device driver first appeared in
.Fx 4.0 .
.Ox
support was added in
.Ox 2.7 .
A version of the driver based on the one in
.Nx
was added in
.Ox 3.9 .
.Sh AUTHORS
.An -nosplit
The
.Nm
driver was written by
.An Bill Paul Aq Mt wpaul@ee.columbia.edu
and ported to
.Ox
by
.An Michael Shalayeff Aq Mt mickey@openbsd.org .
Later the
.Nx
version of the driver by
.An Atsushi Onoe
was subsequently ported to
.Ox
by
.An Jonathan Gray Aq Mt jsg@openbsd.org .
.Sh CAVEATS
Scanning for access points is not currently supported.
